Patent Translate Powered by EPO and Google Notice This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate, complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or financial decisions, should not be based on machine-translation output. DESCRIPTION JPH01125200 [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bolt-clamped Langevin type vibrator, and more particularly to a vibrator with excellent temperature characteristics. (Prior Art) Metal blocks are disposed on both end faces of an annular electrostrictive vibration element consisting of a combination of a piezoelectric element and a terminal plate, and these are inserted through the inside of the electrostrictive vibration element. Bolted Langevin type vibrators in which both ends are integrated with a pair of metal blocks by a central bolt made of gold If4 are known, and in fields intended for ultrasonic application, machine tools or mixing 1 dispersion, including cleaning of various articles It is widely used. (Problems to be Solved by the Invention) However, when cleaning the article by immersing the vibrator in a high temperature liquid, a void is generated due to the difference in thermal expansion between the metal block and the electrostrictive vibration element, and There is a problem that the sound wave characteristics deteriorate. That is, an aluminum alloy is generally used as a material of a pair of metal blocks and a central bolt in order to improve vibration radiation. Although a selection of magnesium alloy, titanium alloy, nickel chrome steel or more is selected and used, the center bolt and the pair of metal blocks may be selected from materials having similar linear expansion coefficients or similar materials. Is easier to stretch due to its elongated shape than the metal block, which loosens the connection between the metal block and the electrostrictive vibration element, creates a gap, degrades the temperature characteristics, and significantly reduces the ultrasonic characteristics, especially at high temperatures. . An object of the present invention is to solve the above-mentioned problems and to provide a vibrator having excellent temperature characteristics. (Means for Solving the Problems) According to the present invention, an annular electrostrictive vibration element, a pair of metal blocks having screw holes in the center in contact with both end surfaces of the electrostrictive vibration element, and the annular electrostriction The present invention relates 04-05-2019 1 to a high temperature bolted Langevin type vibrator composed of a ceramic center bolt which is inserted through the inside of a vibrating element and screwed and fixed to a screw hole of each metal block. In the present invention, annular electrostrictive vibration! ! The element is formed by alternately laminating a piezoelectric element and a terminal plate, and the piezoelectric element uses a known material such as lead zirconate titanate (PZT) or the like, and the terminal plate uses a phosphor bronze plate or the like. The metal block is also selected from well-known vibration radiative metals such as the aluminum alloy described above. The central bolt made of ceramic is not particularly limited in its type K, but silicon carbide or silicon nitride is preferable in terms of high temperature strength. (Operation) For example, when silicon carbide is used for the central bolt and aluminum is used for the metal block, the #I expansion coefficient is compressed by the metal block by a rise of two because silicon carbide is a fraction of aluminum. There is no gap between the electrostrictive vibration element and the metal block. EXAMPLES The present invention will now be described in detail. FIG. 1 is a cross-sectional view showing a high temperature bolted Langevin anti-oscillator according to an embodiment of the present invention. In the figure, 1 denotes an annular electrostrictive vibration element, and a PZT sintered body of 30 mmφ × 1lanφ × 5 is polarized in the thickness direction to impart electrostrictive properties, and a pair of piezoelectrics whose positive end faces face each other inside With element 1a, la '. It consists of a phosphor bronze plate of 30.5armφX11mmφX0.2mmt, and the pressure 1! It is comprised from the terminal end 1b inserted between elements and the terminal board 1c and lc 'distribute ¦ arranged to the negative electrode side (outer side) end surface. 2 and 3 are in contact with both negative electrode side end faces of the electrostrictive vibration element 1, and fl # tension coefficient (25 to 300 ° C.) provided with screw holes 2a and 3a drilled in the center of the contact surface Is a metal block of a high strength aluminum alloy of 30 mmφ x 42 rrml with 24 × 10-'/ "C, and 4 is a silicon carbide sintered body having a coefficient of linear expansion (25-300C) of 4.2 × 10" 6 / ° C. They are studs (center bolts) provided with male screws 4a and 4btj [MIOX effective screw length attack 120-male threads 4a and 4btj] at both ends of the total length 50 + mn. The male screw 4a was screwed into the screw hole 2alC of the metal block 2, and the screw hole 3a of the metal block 3 was screwed together by a male torque 4bK 500 kg · country torque to form a vibrator. The mechanical Q from normal temperature to 160 ° C. was measured for the photographing moving element by an admittance measuring device set to an east condition of an input voltage iov and a resonance frequency of 28 KHz. As a result, as shown in FIG. 2, the average reduction rate of mechanical Q from normal temperature to 160 ° C. was only about 10 inches. In the above embodiment, electrostrictive vibration g! Although two annular piezoelectric elements and three annular terminal plates are combined as elements, one piezoelectric element may be used, and a large number of pressure T! A combination of an L element and a terminal plate may be used. (Effects of the Invention) The vibrator of the present invention is excellent in ultrasonic characteristics (mechanical Q) even at high temperatures, and is suitable for use as a 04-05-2019 2 vibration source of an ultrasonic cleaner or the like. [0002] Brief description of the drawings [0003] FIG. 1 is a longitudinal sectional view of a high temperature bolted Langevin type vibrator according to the present invention, and FIG. 2 is a graph showing the relationship between the temperature of the vibrator of FIG. 1 and mechanical Q. Explanation of symbols 1 ··· Electrostrictive vibration element 2 ··· Leather key $ metal block 3 ··· Section dark metal block 4 ··· Center bolt 4b1. Electric next shooting S 孕 East 2.3: f A ヮ O ヮ Z 仝: ホ し ホ 2 二 ('C) second figure 04-05-2019 3
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